Klinsmann reality check for euphoric US

US German coach Juergen Klinsmann looks on during a Round of 16 football match between Belgium and USA at Fonte Nova Arena in Salvador during the 2014 FIFA World Cup on July 1, 2014

Jurgen Klinsmann welcomed the euphoria around the United States' World Cup performances Wednesday but he warned the team is still a work in progress.

The German coach said he was proud of his players, including back-to-the-wall goalkeeper Tim Howard, after the US team went down all guns blazing against Belgium in the last 16.

But he was rueful about the 2-1 extra-time defeat -- and said he did not hold back when critiquing his players after the dramatic game in Salvador.

"When you go out in the round of 16 clearly you have a lot of work ahead of you," Klinsmann told reporters at the team's training base in Sao Paulo.

"There's still a sense of too much respect... it's still a mentality topic that we're working on in training, of not giving an opponent the first move all the time."

"We could have turned that game around in extra time. We had enough chances in extra time so why not do it earlier?" he added.

The USA attracted record TV audiences for football in their home country with President Barack Obama, watching on Airforce One, a notable fan.

Howard in particular attracted social media buzz for his defiance which repeatedly kept the team alive against Belgium before they scored twice in a gripping extra-time.

But Klinsmann said he told his team: "Listen, if you had put that ball in the net yesterday we would be in the next round. So think about that a second.

"Without making it too harsh, they need that sense of accountability, a sense of criticism and that people around them care about it."

However, Klinsmann also said the United States, who were turned down for friendlies before the World Cup, had earned respect from more established football powers.

"I think now after the World Cup a lot of countries look at us differently. They will give us a game," he said.

"Whether it's South American countries or European countries, they're not taking us lightly any more. We're building that respect."

Klinsmann said the USA, currently ranked 13th, had ambitions to break into the world's top four or eight countries -- but would need work on all levels, from players to referees to their football leagues.

"I think we can only grow. Our upside is far bigger than a lot of countries' so the game is breaking through on all levels," he said. "But we have to help the game grow on many different levels."

Klinsmann said the US campaign had suffered from the loss to injury during game one of striker Jozy Altidore, which meant the team often sat too deep and invited attacks.

And he acknowledged the hype surrounding the bearded Howard, who made a tournament-record 16 saves in a performance that could become career-defining.

"That's what soccer can do to you," Klinsmann said.

"It's fantastic because all the games of the World Cup were received at home, more people watched this competition than four years ago in South Africa.

"It's fun to see that and he deserves a compliment for his game last night."